立德树人视域下基于OBE理念的“传热学”课程思政教学探索

文章首先阐述了“传热学”课程教学中存在的问题,然后论述了立德树人视域下基于OBE理念的“传热学”课程思政教学策略,包括挖掘基于OBE理念的思政元素、设计融入思政元素的教学内容、创新以思政效果为导向的教学方法、优化以教学产出为主导的多元考核(评价)方式。

基于慕课视角的辽宁省跨校修读学分探析——以辽宁石油化工大学“传热学”课程为例

慕课教学模式不仅是对传统教学模式的一次重要改革和创新,而且也是实现跨校修读学分改革的重要基础之一。首先,简要介绍了我国教育教学模式的本质因素和发展历程,在此基础上,分析了教学模式发展历程及各阶段存在的主要问题。以辽宁石油化工大学"传热学"跨校修读学分工作为例,指出了跨校修读学分工作实施思路,共包含三个环节,即准备环节、实施过程环节以及验收考核环节。最后,分别对课程实施依据、教学方法与教学策略以及实施过程中应注意的环节等三个方面进行了探析,以期为辽宁省大学生跨校修读学分的全面实施提供一定的依据和参考。

“传热学”系列课程分级教学改革与实践

基于国内外“传热学”系列课程开设情况与当前人才培养的需要,提出了“传热学”系列课程分级教学理论并进行了改革实践。针对“传热学”教学内容与学时不匹配、知识面与不同专业需求矛盾等问题,分别从教学内容体系、教学资源建设以及教学效果多元评价调控等方面着手,深化教学模式改革,形成多样化的通专融合教育模式,有效满足了工科类不同专业的“传热学”系列课程的教学需求。

新工科背景下课程思政在“传热学”课程中的实践

文章首先阐述了新工科背景下课程思政在“传热学”课程中实践的思路,然后论述了新工科背景下课程思政在“传热学”课程中实践的尝试,最后提出了新工科背景下课程思政在“传热学”课程中实践的开展。

“传热学”实验教学的现状与改进

为了有效提升“传热学”实验教学质量,文章首先分析了“传热学”实验教学的现状,然后论述了“传热学”实验教学的改进,包括“传热学”实验教学的改进思路、“传热学”实验教学的改进措施、“传热学”实验教学质量评价。

传热学传统教学的瓶颈和突破刍议

多年来教学活动所积累的经验表明:传热学课程传统教学模式在教学对象、教学内容以及教学方法等诸多方面都存在一定问题。通过逐一剖析表明,传热学传统教学瓶颈在于未将理论教学与工程实际有机融合,工程应用与专业理论的脱节导致了师生间教与学的障碍。在此基础上,明确了实施双向互动、强化对学生进行方法和思维的训练、弱化理论的推导和知识点的灌输是解决这一问题的有效途径。为此,通过裁剪和调整教学内容,构建理论联系实际的教学体系模块,导读式法施教,达到充分调动学生学习的积极性、提高教学水平的目的。

工程认证背景下机械专业《传热学》课程教学改革浅析

《传热学》是机械专业重要的专业基础课程,对其教学改革的研究已比较普遍,但是针对工程认证背景下传热学课程教学改革的研究还较少。基于工程认证的教学理念和教学模式,对“传热学”课程教学所存在问题和改革措施进行了浅析。

石油工程专业“传热学与传质学”课程思政教学策略

文章首先论述了相关背景,然后阐述了石油工程专业“传热学与传质学”课程思政教学策略,包括改革教学模式、融入思政元素、强化实践活动、创新评价机制、突出价值引领五个方面。

NUMERICAL PREDICTION OF AIRCRAFT HYDRAULIC SYSTEM BASED ON THERMAL DYNAMIC ANALYSIS

A mathematical model of principal elements of the aircraft hydraulic system is presented based on the heat transfer theory. The dynamic heat transfer process of the hydraulic oil and the pump shells within an aircraft hydraulic system are analyzed by the difference method. A kind of means for the prediction to variational trends of the aircraft hydraulic system temperature is provided during operation. The numerical prediction and simulation under the operational conditions are presented for ground trial running and the decelerated operation in flight. Computational results show that there is a good coincidence between the experimental data and the numerical predictions.

Mathe matical model and calculation for heat transfer during condensation on surfaces of corrugated plates

A mathematical model was established for condensation on surfaces of verticalcorrugated plates based on the mechanism of heat transfer enhancement to thin down the liquid filmdue to surface tension effect between corrugated plate surfaces and liquid films. The relative heattransfer coefficients of condensation on corrugation plates were calculated in contrast withequivalent vertical plane ones. The heat transfer enhancement effects for the main geometricparameters such as pitch, height, corrugation angle, tilt angle, and fillet radii of corrugationswere analyzed to guide the optimization of corrugation structure for application. A two-scalecorrugation is suggested, which can compromise both the enhanced heat transfer effect and adequatecross section area for flows, and it makes the heat transfer coefficient 1 to 2 times more than thatof an equivalent plane one.

A New Heat-conduction Logging Technique and its Application

The results of a heat-conduction experiment with a central point source in a sand barrel shows that the temperature of the heat source increase much faster in sand saturated with oil and air （dry sand） than in water sand. During cooling the temperature of the central heat source goes down slower in oil- or air-saturated sands than in water sands. Based on the theory of heat-conduction in porous media and the experimental results, we developed a new heat-conduction logging technique which utilizes an artificial heat source （dynamite charge or electric heater） to heat up target forma- tions in the borehole and then measure the change of temperature at a later time. Post-frac oil production is shown to be directly proportional to the size of the temperature anomaly when other reservoir parameters are fairly consistent. The method is used to evaluate potential oil production for marginal reservoirs in the FY formation in Song-Liao basin of China.

Pollination Biology of Ficus hispida in the Tropical Rainforests of Xishuangbanna, China

Ficus hispida L. (Moraceae) is a remarkable species in the ecosystem of tropical rainforests in Xishuangbanna, China. The figs and fig_pollination wasps (Chalcidoidae: Agaonidae) are highly co_evolved mutualists that depend completely on each other for propagating descendants. Pollination of all fig species is done by fig wasps; their unique symbiotic associates, the fig wasps, cannot develop in anywhere except in the fig syconia. The present paper reports on the biology and flowering phenology of F. hispida , as well as the propagation character and pollination behavior of the fig wasps (Ceratosolen solmsi marchali Mayr) based on our observations in the rainforests of Xishuangbanna, southern Yunnan of China. F. hispida is a dioecious tree that annually blossoms and bears fruits 6-8 times, with four to five fruit_bearing peaks. The male trees produce pollen and provide fig wasps with reproductive havens, while the female trees produce fig seeds after pollination by the female wasps. Pollen of F. hispida cannot escape from the dehiscent anthers until they are disturbed by fig wasps. The female wasps open the anthers and collect pollen with their antennal scrapes, mandibles and legs, and then carry pollen to the female receptive syconia where fertilization takes place. Meanwhile, some of the female wasps lay eggs in the male receptive syconia. It takes about 3-67 min to search for the receptive syconia for pollination, and 15-23 h to enter the female receptive syconia. The number of female wasps entering a syconium has close relation with the impregnation and seed_bearing rate of female flowers, as well as the oviposition and reproduction rate of the fig wasps themselves. F. hispida is endowed with a relatively high level of seed bearing (54.1%-82.5%, average 73.8 %). The wasp oviposition rate on the male flowers is between 72.3% and 93.8% with a mean of 84.4%.

Air interaction around outdoor air-cooled condensers

In order to increase cooling or heating efficiency,a porous computational fluid dynamics（CFD）model is employed to predict the thermo-fluid status and optimize the placement of outdoor units.A full scale model is established to validate the accuracy of CFD simulation in terms of velocity and temperature distributions.The comparison between the measurement and the simulation shows a good agreement.By evaluating the condensers＇ sucked air temperature with CFD for three units installed in a row,it is found that the minimum separation distance among neighboring units is 0.2 m;a vertical wall should be apart from the unit line by at least 0.8 m;and large different operating pressures among units do not impact the flow rate and the heat transfer of the other units meaningfully.

FIBER OPTIC TEMPERATURE MEASURING SYSTEM

This paper presents a fiber optic temperature measuring system used for measuring the temperature in many occasions. The system is of reflective type and composed of thermostatic bimetal plate, lever piston framework, optical grating and optical fiber probes. When the temperature changes, the thermostatic bimetal plate deforms. Through lever piston framework, the optical grating produces displacement in the upright direction. Thus the change of the temperature is transformed into the upright displacement of the optical grating. Optical fiber probes are used for detecting the number of streak lines of the optical grating′s displacement depending on the change of temperature. The detected signal can be transmitted to the control center through optical fiber cable up to distance of 1 km. The measurable range of this system reaches 100℃ with accuracy of ±0.2℃.

Experimental and CFD Heat Transfer Studies of Al2Oa-Water Nanofluid in a Coiled Agitated Vessel Equipped with Propeller

This paper presents the heat transfer characteristics of A1203-water nanofluid in a coiled agitated vessel with propeller agitator. The experimental study was conducted using 0.10%, 0.20% and 0.30% volume concentra tion of A1203-water nanofluids. The results showed considerable enhancement of convective heat transfer using the nanofluids. The empirical correlations developed for Nusselt number in terms of Reynolds number, Prandtl number, viscosity ratio and volume concentration fit with the experimental data within ±10%. The heat transfer characteris tics were also simulated using computational fluid dynamics using FLUENT software with the standard ke model and multiple reference frame were adopted. The computational fluid dynamics （CFD） predicted Nusselt number agrees well with the experimental value and the discrepancy is found to be less than ＋8%.

Application of fiber Bragg grating sensor network in aluminum reduction tank shell temperature monitoring

A fiber Bragg grating temperature sensor network was designed to implement the real-time health monitoring of the aluminum reduction cell. The heat transfer process was simulated using software ANSYS, and an on-line shell monitoring system was established based on optical sensing technology. According to aluminum reduction cell heat transfer theory, the 2D slice finite element model was developed. The relationship between shell temperature and cell status was discussed. Fiber Bragg grating （FBG） was chosen as the temperature sensor in light of its unique advantages. The accuracy of designed FBG temperature sensors exceeds 2 ~C, and good repeatability was exhibited. An interrogation system with 104 sensors based on VPG （volume phase grating） filter was established. Through the long-term monitoring on running state, the status of the aluminum reduction cell, including security and fatigue life could be acquired and estimated exactly. The obtained results provide the foundation for the production status monitoring and fault diagnosis. Long-term test results show good stability and repeatability which are compatible with electrolysis process.

Numerical simulation of hydrothermal mineralization associated with simplified chemical reactions in Kaerqueka polymetallic deposit, Qinghai, China

The Kaerqueka polymetallic deposit, Qinghai, China, is one of the typical skarn-type polymetallic ore deposits in the Qimantage metallogenic belt. The dynamic mechanism on the formation of the Kaerqueka polymetallic deposit is always an interesting topic of research. We used the finite difference method to model the mineralizing process of the chalcopyrite in this region with considering the field geological features, mineralogy and geochemistry. In particular, the modern mineralization theory was used to quantitatively estimate the related chemical reactions associated with the chalcopyrite formation in the Kaerqueka polymetallic deposit. The numerical results indicate that the hydrothermal fluid flow is a key controlling factor of mineralization in this area and the temperature gradient is the driving force of pore-fluid flow. The metallogenic temperature of chalcopyrite in the Kaerqueka polymetallic deposit is between 250 and 350 ℃. The corresponding computational results have been verified by the field observations. It has been further demonstrated that the simulation results of coupled models in the field of emerging computational geosciences can enhance our understanding of the ore-forming processes in this area.

Crystallization Thermodynamic and Kinetic Behaviors of Vitamin C in Batch Crystallizer

The bench-scale cooling crystallization for ternary solution of L-ascorbic acid (Vitamin C) was studied.The solid-liquid phase diagram of Vitamin C-water-ethanol system was obtained on the basis of differential scanning calorimeter (DSC) curves. The heat of crystallization of Vitamin C was calculated with the aid of quantitative analysis. According to the population balance equation under unsteady state, the rates of nucleation and growth were determined. The parameters of crystallization kinetics equations were estimated by regression of experimental data. Crystal morphology and size were determined with x-ray diffraction and TA Ⅱ Coulter Counter.

Comparison on Thermal Conductivity and Permeability of Granular and Consolidated Activated Carbon for Refrigeration

This paper focuses on the development of three types of activated carbon （AC） adsorbents, i.e. granular AC, consolidated AC with chemical binder, and consolidated AC with expanded natural graphite （ENG）. Their thermal conductivity was investigated with the steady-state heat source method and the permeability was tested with nitrogen as the gas source. Results show that the thermal conductivity of granular AC with different sizes al-most maintains a constant at 0.36 W-（m.K）-＇, while the value modestly increases to 0.40 W.（m.K）-＇ for the con- solidated AC with chemical binder. The consolidated AC with ENG at the density of 600 kg. m-3 shows the best heat transfer performance and their thermal conductivity vary from 2.08 W-（m.K）- to 2.61 W. （m.K）-1 according toits fraction of AC. However, the granular AC and consolidated AC with chemical binder show the better permeabil- ity performance than consolidated AC with ENG binder whose permeability changes from 6.98x10-13 m2 to 5.16x10TM m2 and the maximum occurs when the content of AC reaches 71.4% （by mass）. According to the differ- ent thermal properties, the refrigeration application of three types of adsorbents is analyzed.

Ground-State and Thermal Entanglement in Three-Spin Heisenberg-XXZ Chain with Three-Spin Interaction

The entanglement properties of a three-spin X X Z Heisenberg chain with three-spin interaction are studied by means of concurrence of pairwise entanglement. We show that ground-state pairwise entanglement, pairwise thermal entanglement, or quantum phase transition is not present in antiferromagnetic spin chain. For the ferromagnetic case, quantum phase transition takes place at A = 1 for anisotropic interaction and at some values of three-spin coupling strength, and pairwise thermal entanglement increases when the value of J/T increases and with anisotropic interaction and three-spin interaction decrease. In addition, we find that increasing the anisotropic interaction and the three-spin interaction will decrease critical temperature.